The present invention relates to a resin component formed by vibration welding together first and second molded bodies that are both molded from a synthetic resin.
Conventionally, the aforesaid resin component is known in, for instance, Japanese Patent Unexamined Publication No. Hei. 7-266425, and in the resin component disclosed therein, in order to prevent a damage to the commercial value of the resin component by burrs that are produced to be exposed from an external surface of the resin component when the fist and second molded bodies are vibration welded together, a flat joint area is provided on one of the two molded bodies, while provided on the other molded body are a welding projection adapted to be vibration welded to the joint area at a distal end thereof and a regulating projection disposed outwardly of the vibration welding portion and adapted to abut against the joint area when vibration welding of the vibration welding portion to the joint area is completed, so that burrs produced to project outwardly when the welding projection is vibration welded to the joint area are contained within a space formed between the welding projection and the regulating projection to thereby be prevented from exposure to the outside.
In the above-described conventional resin component, since there exists a gap between the regulating projection and the joint area before the vibration welding is completed, burrs produced in conjunction with vibration welding of the welding projection to the joint area before the vibration welding is completed are guided by the flat guide surface to be exposed to the outside through the gap, this leading to a possibility that the burrs are exposed to the outside or held between the regulating projection and the joint area after the vibration welding is completed, thus it being not possible to securely prevent the exposure of the burrs to the outside.
The present invention was made in view of the problem described above, and an object thereof is to provide a resin component in which exposure of burrs produced when first and second molded bodies are vibration welded to the outside is securely be prevented to thereby improve the commercial value of the resin component.
The above-mentioned object can be achieved by a resin component according to the present invention comprising a first synthetic resin molded body and a second synthetic resin molded body coupled with the first synthetic resin molded body by a vibration welding. The first resin molded body includes an joint area which is provided at its edge portion where the first molded body is joined to the second molded body, a first regulating projection which is provided from an outermost edge of the joint area toward the second molded body, and a first guide surface connecting an internal side surface of the first regulating projection to the joint area. The second resin molded body includes a welding projection which is projected toward the first molded body so as to be welded at a distal end thereof to the joint area of the first molded body and is provided at its edge portion where the second molded body is jointed to the first molded body, a second regulating projection which is projected from an outermost edge of the second molded body toward the first molded body so as to closely confront the first regulating projection after a vibration welding operation between the welding projection and the joint area is completed, and a second guide surface connecting an external side surface of the welding projection to an internal side surface of the second regulating projection.
In the resin component according to the present invention, it is preferable that the first guide surface is formed into a curve shape to guide a burr produced to project toward the first regulating projection as a result of vibration welding of the welding projection to the joint area toward the internal side surface of the second regulating projection along the internal side surface of the first regulating projection, and the second guide surface is curved and located in confront with the first guide surface so as to guide the burr guided from the internal side surface of the first regulating projection to the internal side surface of the second regulating projection toward the external side surface of the welding projection.
In addition, in the resin component according to the present invention, it is also preferable that each of the joint area, the first regulating projection, the welding projection and the second regulating projection is formed into an endless shape.
Further, in the resin component according to the present invention, it is advantageous that the distal end of the welding projection has a cross section substantially formed by two line one of which is inclined relative to a direction extended perpendicular to the joint area by a first predetermined angle (xcex1) and the other of which is extended along or inclined relative to the direction by a second predetermined angle (xcex2) smaller than the first predetermined angle.
Moreover, in order to attaining the above object, according to the present invention, there is provided a resin component formed by vibration welding together first and second molded bodies that are molded from a synthetic resin, wherein there are provided at an edge portion of the first molded body where the first molded body is joined to the second molded body an endless joint area, a first endless regulating projection projecting from an outer edge of the joint area toward the second molded body and a first guide surface connecting an internal side surface of the first regulating projection to the joint area, wherein there are provided at an edge portion of the second molded body where the second molded body is jointed to the first molded body, an endless welding projection projecting toward the first molded body in such a manner as to be welded at a distal end thereof to the joint area of the first molded body, a second endless regulating projection projecting from an outer edge of the second molded body toward the first molded body in such a manner as to closely confront the first regulating projection when vibration welding of the welding projection to the joint area is completed and a second guide surface connecting an external side surface of the welding projection to an internal side surface of the second regulating projection, the first guide surface being curved convexedly outwardly in such a manner as to guide a burr produced to project toward the first regulating projection as a result of vibration welding of the welding projection to the joint area toward the internal side surface of the regulating projection along the internal side surface of the first regulating projection, and the second guide surface being curved convexedly to a side opposite to the first guide surface in such a manner as to guide the burr guided from the internal side surface of the first regulating projection to the internal side surface of the second regulating projection toward the external side surface of the welding projection.
According to the above construction, the first and second molded bodies are vibrated relative to each other at a high speed with the distal end of the welding projection of the second molded body being pressed against the joint area of the first molded body, whereby the distal end of the welding projection is vibration welded to the joint area by a friction heat produced between the distal end of the welding projection and the joine area to thereby construct the resin component. Of burrs produced at a contact portion between the distal end of the welding projection and the joint area during this vibration welding, those projecting outwardly are guided by the first guide surface along the internal side surface of the first regulating projection toward the second regulating projection, and furthermore burrs guided from the internal side surface of the first regulating projection to the internal side surface of the second regulating projection are then guided toward the external side surface of the welding projection by the second guide surface, and therefore the burrs are prevented from project outwardly from the gap between the first and second regulating projections and instead they are destined to be confined within the space formed by the joint area, the first regulating projection, the second regulating projection and the welding projection, whereby exposure of the burrs from the external surface of the resin component is securely prevented, this thereby contributing to the improvement of the commercial value of the resin component so formed.